The space-frame antenna is a conceptual antenna structure that would be lightweight, deployable from compact stowage, and capable of deforming itself to a size, shape, and orientation required for a specific use. The underlying mechanical principle is the same as that of the amorphous rover described in the immediately preceding article: The space-frame antenna would be a trusslike structure consisting mostly of a tetrahedral mesh of nodes connected by variable-length struts. (The name of the antenna reflects the fact that such a structure has been called a “space frame.”) The deformation of the antenna to a desired size, shape, and orientation would be effected through coordinated lengthening and shorting of the struts. In principle, it would even be possible to form the space-frame antenna by deforming another space-frame structure (e.g., the amorphous rover) in this manner.
Typically, the space-frame antenna would be configured as a dish-type reflector with an arm holding a receiver, all on a steerable base. Examples of exploiting the space-frame concept to reconfigure the antenna for a specific use include making the base taller (for viewing over obstructions) and making the dish wider (for greater sensitivity), as illustrated in the figure.
Like the amorphous rover, the space-frame antenna could be designed and built using currently available macroscopic electromechanical components or by exploiting microelectromechanical systems (MEMS), nanoelectromechanical systems (NEMS), or perhaps even carbon nanotubes. An initial version made from currently available components would likely have an areal mass density of the order of 1 kg/m2. Moreadvanced versions made from MEMS, NEMS, or nano - tubes could have areal mass densities ranging from about 100 to as little as 10 g/m2. Also as in the case of the amorphous rover, any or all of these versions could include control systems based partly on evolvable neural software systems.
This work was done by Steven A. Curtis of Goddard Space Flight Center. For further information, contact the Goddard Innovative Partnerships Office at (301) 286-5810. GSC-14849-1